Electronically controlled sewing machines of the type using electronic logic to control the sewing instrumentalities, such as, for example, the needle mechanism and the feed control mechanism, are in and of themselves known in the art. See, for example, U.S. Pat. No. 3,855,956, issued Dec. 24, 1974, and U.S. Pat. No. 3,984,745, issued Oct. 5, 1976, both of which are assigned to the same assignee as the present invention. Machines of this type have gained a relatively rapid and popular acceptance in the market place and have many desirable features.
Machines having cam controlled feed mechanisms wherein feed stitch position coordinates are provided mechanically through a cam and a cam follower regulating the extent and direction of feed, are also well known in the art. See for example, U.S. Pat. No. 3,585,876, issued July 22, 1971, and U.S. Pat. No. 3,636,900, issued June 25, 1972, both of said patents also being assigned to the same assignee as the present invention. Such cam controlled feed mechanisms have proven to be desirable in that they are relatively durable and are able to absorb the variable feed back forces generated by fabrics of different thicknesses and densities which may be sewn on the machine and thereby prevent such forces from having a deleterious effect on the operation of the feed mechanism. Also, with respect to manually selectable cam controlled feed mechanisms, the feature of being able to manually select some feeding features is desirable.
It is an object of the present invention to provide an improved sewing machine which has incorporated therein the desirable features of the electronically controlled needle position coordinates and which has a manually selectable cam controlled feed mechanism with the advantages enumerated above. A combination of this type, results in a machine which has a very durable mechanism in the area wherein durability is desired and an electronic automatic mechanism wherein accuracy and intricacy of control is desired. In accordance with the invention means are provided enabling an operator to selectably combine cam controlled feed patterns with any one of the electronically controlled needle patterns to produce a variety of stitch patterns. Other objects and advantages of the invention will be best understood when reading the following detailed description with the accompanying drawings wherein: